Cage and ball bearing comprising the cage

This application claims priority to Chinese Application No. 202211088231.3, filed Sep. 7, 2022, the entirety of which is hereby incorporated by reference.

The present disclosure relates to a cage and a ball bearing comprising the cage.

Ball bearings, especially deep groove ball bearings, are widely used in various fields. A traditional cage for a deep groove ball bearing includes, for example, a steel cage with a wave profile requiring riveting connection, a one-piece polymer prong-type cage, and so on. A window type cage is difficult to be applied to a deep groove ball bearing due to the assembling process of such cage. However, the steel cage is heavy, requires a complicated assembling process (involving riveting connection) and not suitable for high-speed applications. While the one-piece polymer prong-type cage has a semi-enclosed structure, which is lighter in weight and simple in assembling, but it is not suitable for high-speed applications either. For example, in some bearing applications that require high operation speeds, the cages will suffer from an umbrella effect.

Taking the deep groove ball bearing as an example, please refer to. As the speed is increasing, prongs of the one-piece polymer prong-type cage (also known as one-way insert cage) tend to expand and deform outward under centrifugal force, causing the so-called “umbrella effect”. The umbrella effect will destroy the matching relationship between the pockets and the balls, causing interference between the pockets and the balls, thus leading to local overheating of the cage. What's more, severe umbrella effect under high speeds will cause the balls dropping-off from the cage, and the bearing will be stuck, which will lead to failure of related systems.

In addition, the prongs of the one-piece polymer prong-type cage allow large deformation so as to meet the needs of assembling process. However, such deformation operation on the cage is usually considered as risky, since it may cause the prongs of the cage to break.

In view of this, the present disclosure provides a cage, comprising: a first sub-part, comprising a plurality of first partitions integrated as a whole and a plurality of first pocket portions formed by adjacent first partitions; a second sub-part, comprising a plurality of second partitions integrated as a whole and a plurality of second pocket portions formed by adjacent second partitions, wherein a pocket is formed by the first pocket portion and the corresponding second pocket portion; wherein, a first recess is provided on the first partition belonging to a first set of the plurality of first partitions, and a second pin extend along an axial direction from the second partition belonging to a second set of the plurality of second partitions, and the second pin is fixed in its corresponding first recess; wherein, the first set of first partitions comprises any one or more of the plurality of first partitions, and the second set of second partitions comprises any one or more of the plurality of second partitions and correspond to the first set of first partitions respectively.

The cage of the present disclosure overcomes the harmful umbrella effect found in the one-piece polymer prong-type cage, so that the bearing equipped with the cage of the present disclosure can operate under very high speeds. Moreover, since the structural stiffness of the cage of the present disclosure is higher, the stress at critical locations is lower, and due to its fully enclosed pocket design, it can deal with very harsh bearing working environment and bearing working requirements in comparison with the prong-type cage.

In order to make the purpose, technical solution and advantages of the technical solution of the present disclosure clearer, the technical solution of the embodiment of the present disclosure will be described clearly and completely in the following with the attached drawings of specific embodiments of the present disclosure. Like reference numerals in the drawings represent like components. It should be noted that a described embodiment is a part of the embodiments of the present disclosure, not the whole embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by those skilled in the field without creative labor fall into the scope of protection of the present disclosure.

In comparison with the embodiments shown in the attached drawings, feasible embodiments within the protection scope of the present disclosure may have fewer components, other components not shown in the attached drawings, different components, components arranged differently or components connected differently, etc. Furthermore, two or more components in the drawings may be implemented in a single component, or a single component shown in the drawings may be implemented as a plurality of separate components.

Unless otherwise defined, technical terms or scientific terms used herein shall have their ordinary meanings as understood by those skilled in the field to which this disclosure belongs. For example, similar words such as “including” or “comprising” mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. “Up”, “down”, “left” and “right” are only used to indicate the relative orientation relationship when the equipment is used or the orientation relationship shown in the attached drawings. When the absolute position of the described object changes, the relative orientation relationship may also change accordingly.

For the convenience of explanation, the direction of the rotation axis of the bearing to which the cage is applied is called an axial direction, the direction perpendicular to the axial direction is called a radial direction, and the direction along the rotation direction of the bearing is called the circumferential direction. The term “inner/inward” refers to the direction toward the inside of the relevant component, whereas the term “outer/outward” refers to the direction toward the outside of the relevant component.

Referring to the preferred embodiment of, the present disclosure provides a cage comprising a first sub-partand a second sub-partwhich are assembled oppositely along an axial direction and fixed together. In this embodiment, the cage is suitable for ball bearings, especially for deep groove ball bearings.

The first sub-partcomprises a plurality of first partitionsintegrated as a whole and a plurality of first pocket portionsformed by the adjacent first partitions. Accordingly, the second sub-partcomprises a plurality of second partitionsintegrated as a whole and a plurality of second pocket portionsformed by adjacent second partitions. A pocketis formed by the first pocket portionand its corresponding second pocket portion, as shown in, and the pocket is used for holding a ball.

Furthermore, a first recessis provided on the first partitionbelonging to a first set of the plurality of first partitions, and a second pinextends along the axial direction from the second partitionbelonging to a second set of the plurality of second partitions, and the second pinis fixed in its corresponding first recess. It should be understood that the “fixation” can be achieved by any suitable fixation method, such as welding, adhesion bonding, snap fit, etc.

The term “set” used here and after indicates some or all items selected from a plurality of related items, so it can also be understood as the meaning of “group”. Therefore, the first set of first partitionscomprises any one or more of the plurality of first partitions, and the second set of second partitionscomprises any one or more combination of the plurality of second partitionsand should correspond to the first set of first partitionsrespectively, thus ensuring that the first recessand the second pincan be fixed together accurately. In the preferred embodiment shown in, the first set includes all the first partitionsand the second set includes all the second partitions. However, in an embodiment not shown, according to the number of the first partitions and second partitions and the assembly requirements of the cage, the first set may comprise at least two first partitionsevenly spaced, and correspondingly, the second set may comprise at least two second partitionsevenly spaced, for example.

When the cage is used for assembling a bearing, one can firstly put the balls into the pockets of one of the sub-parts, and then assemble the other sub-part to the sub-part containing the balls. The assembling process involves aligning the first recesses with the second pins, inserting the second pins into the first recesses, and then fixing the two sub-parts together, to form a cage fully enclosing the balls.

In comparison with the one-piece polymer prong-type cage of the prior art, the cage of the present disclosure eliminates the pocket openings and prongs, and realizes a full enclosure of the balls. Especially during the operation of the deep groove ball bearing, the deformation of the cage of the present disclosure is smaller, the umbrella effect can be effectively avoided, and the cage can be prevented from popping out when the bearing rotates at high speeds. Therefore, extremely high rotary speeds of the deep groove ball bearing can be realized. Moreover, this cage can also reduce stress and strain on edges, thus reducing fracture of the edges. In addition, when the bearing is in operation, the cage can guide the balls better and absorb more vibration.

On the other hand, although the material selection for the first and second sub-parts is not particularly limited, it is preferable that, in this embodiment and other preferred embodiments described later, the first sub-partand second sub-partare made of polymer materials, such as nylon, PA66, PA6, PEEK, etc. In comparison with the steel cage of the prior art which needs to be fixed by riveting, the cage made of polymer is lighter in weight and has better shock-absorption effect, so it is also beneficial to the application with higher rotary speeds.

It should also be understood that shape of the recess and shape of the pin are not particularly limited (some specific shapes are given in the preferred embodiment hereinafter), and the purpose is to align the first sub-partwith the second sub-partand temporarily assemble them together, to facilitate the subsequent fixing operation.

In the preferred embodiment shown in, the first recessmay be provided as a through hole penetrating through two axial sides (i.e., the axial inner sideand the opposite axial outer side not shown) of the corresponding first partition, so that an end of the corresponding second pinmay be exposed from the through hole. Accordingly, the fixation between the pin and the through hole can be realized by welding, that is, welding the end of the corresponding second pinsto the surrounding portions thereof (this includes welding the end and the surrounding portions of the through hole).

It should be understood that the term “exposed” used above means that the endof the second pinis slightly retracted, flushed or slightly protruded (as shown in) with respect to an axial outer sideof the first sub-part, as long as the “exposed” portion is suitable for welding. In addition, the specific shape of the recess and the pin can be flexibly selected, such as a roughly rounded rectangle shape as shown in, a prism shape, a cylinder shape or the like.

Furthermore, in the case of fixation without welding, for example, the pin and the recess can be adhesively bonded, or the size of the pin and the recess can be set to achieve an interference fit, or a snap-fit structure can be provided at the end of the pin to snap with the end of the recess (or the through hole).

show a further improvement of the preferred embodiment according to the above. In this modified example, in addition to the first recessand the second pin, a first pinextend along the axial direction from the first partitionbelonging to a third set of the plurality of first partitions, and a second recessis provided on the second partition belonging to a fourth set of the plurality of second partitions, and the first pinis fixed in its corresponding second recess. The third set of first partitionscomprises any one or more of the plurality of first partitions, and the fourth set of second partitionscomprises any one or more of the plurality of second partitionsand correspond to the third set of first partitionsrespectively. According to this preferred embodiment, each partition,of the two sub-parts,includes a pin and a recess, and the pin and the corresponding recess can be accurately fixed together. This preferred embodiment can achieve fixation on both sides of the whole cage along the axial direction, so that the cage is more balanced and firmer.

In the preferred embodiment shown in, the first set and the third set contain each other (or are the same), i.e., each of the first and third sets contain all the first partitions; the second set and the fourth set contain each other (or are the same), i.e., each of the second and fourth sets contain all the second partitions. However, it should be understood that the first set and the third set may also have no intersection or have partial intersection, and the second set and the fourth set may have no intersection or have partial intersection, that is, various sets of partitions containing recess(es) and/or pin(s) can be arbitrarily chosen from the first partitionsand the second partitions, for example, according to structural needs, assembling positions, stress requirements, etc., to realize various fixation structures.

Preferably, the second recesscan also be provided as a through hole penetrating two axial sides (i.e., the axial inner sideand the opposite axial outer side not shown) of the second partitions, and an end of the first pinsmay be exposed from the through hole. Accordingly, the fixation between the pin and the through hole can be realized by welding, that is, welding the end of the first pinto the surrounding portions thereof.

It should be understood that, as mentioned above, in the case of fixation without welding, the fixation can also be achieved by adhesive bonding, interference fit or snap-fit.

Preferably, as shown in, the first recessand the first pinon the first sub-partcan be arranged side-by-side along the circumferential direction, and correspondingly, the second pinand the second recesson the second sub-partcan also be arranged side-by-side along the circumferential direction. However, it should be understood that the pins and through holes on each sub-part may have different arrangements, for example, arranged along the radial direction, or arranged along an approximately diagonal direction of the axial sides where they are located.

Further preferably, the first recessand the second recessmay be identical, and the second pinand the first pinmay also be identical. Furthermore, the first sub-partand the second sub-partmay be completely identical. With this structure, the two sub-parts of the cage can be produced by only one mold, which further saves manufacturing cost and assembling cost.

As mentioned above, the first set and the third set may have no intersection, and the second set and the fourth set may have no intersection. For example, in another preferred embodiment of the present disclosure shown in, first recesses (shown schematically by hollow circles) are formed on the first set of partitions, and first pins (shown schematically by solid circles) extend from the third set of first partitionsalong the axial direction.

Accordingly, second pins (shown schematically by hollow circles) extend from the second set of second partitionsalong the axial direction, and second recesses (shown schematically by solid circles) are formed on the fourth set of second partitions. The first recesses and the second recesses may be formed as through holes.

Furthermore, the first recesses of the first set of and first pins of the third set are alternately arranged on the first sub-part, and similarly, the second pins of the second set and the second recesses of the fourth set are alternately arranged on the second sub-part.

During assembly, the second pins of the second set are inserted into the corresponding first recesses of the first set and the end of each second pin is exposed from the corresponding first recess; the first pins of the third set are inserted into the corresponding second recesses of the fourth set and the end of each first pin is exposed from the corresponding second recess. Subsequently, the first sub-partand the second sub-partare fixed together, for example, by welding the end of each first pin and the end of each second pin with their surrounding portions, or by other fixation means.

With this configuration, the first sub-partand the second sub-partmay also be completely identical, that is, the two sub-parts of the cage can be produced by only one mold, which further saves the manufacturing cost and the assembling cost.

The embodiment (in which the first set and the third set are the same or have no intersection, and the second set and the fourth set are the same or have no intersection) has been shown above by the drawings. In other embodiments, as shown in, the first set and the third set may partially intersect, that is, there may be three types of first partitions on the first sub-part, which are:

And these three types of first partitions may be arbitrarily arranged as needed, for example, any type of first partitions may be adjacent to the same or other types of first partitions; in some embodiments, some first partitions may not be provided with any recess or pin.

Accordingly, the second set and the fourth set may also be similarly configured and arranged to partially intersect, so as to correspond to the first set and the third set respectively, which will not be repeatedly described here.

In the embodiments described in, both the recess and the pin are formed in the middle of the corresponding partition, i.e., associated with the axial sides of the partition. In another preferred embodiment according to the present disclosure, the present disclosure provides a fixation structure formed on the radial sides of the partition.

Specifically, as shown in, a first recessmay include an axial through groove at least formed on a radial outer sideof the first partition, and correspondingly, a second pinmay include an axial pin extending along the axial direction from a radial outer sideof the second partition.

Similarly, a second recessmay include an axial through groove at least formed on the radial outer sideof the second partition, and correspondingly, a first pinmay include an axial pin extending along the axial direction from the radial outer sideof the first partitions.

In other embodiments, a first recess may include an axial through groove (not specifically shown) formed on a radial inner sideof the first partition, and a second pin may include an axial pin (not specifically shown) extending along the axial direction from a radial inner sideof the second partition. Similarly, a second recess may include an axial through groove (not specifically shown) formed on the radial inner sideof the first partition, and a first pin may include an axial pin (not specifically shown) extending along the axial direction from the radial inner sideof the second partition.

In the above two configurations, the assembling and fixation of the cage can be realized by fixing the axial pins with the corresponding recesses together. For example, the interfacing seams between the axial pins and the corresponding recesses (including the interfacing seams on the radial sides and the interfacing seams on the axial sides (if any)) may be welded, or connected by adhesive or snap-fit structures.

In addition, in the above-mentioned embodiments, the axial inner side of the first partitionis formed as a flat surface perpendicular to the axial direction, and the axial inner side of the second partitionis formed as a flat surface perpendicular to the axial direction, so that the abutting surfaces between the first partitionand the second partitionare flat surfaces. Furthermore, the present disclosure also provides a modification to the axial sides abutting each other between the first sub-partand the second sub-part, as shown in. For convenience, display of the recess and the pin is omitted from.

Specifically, in the modification of, an axial inner sideof the first partitionis formed as a curved surface, and an axial inner sideof the second partitionis formed as a curved surface matching with the axial inner side. The two curved surfaces may preferably be surfaces in arc shape, or they may have any other curved shape, such as in a shape of wave. By arranging the abutting surfaces in the form of curved surfaces, it can further facilitate the first sub-partand the second sub-partto hold each other and prevent them from being dislocated and deformed along the circumferential direction. In addition, it should be understood that even if such curved surfaces are provided, it will not affect the formation of the recesses and the pins.

According to another modification, as shown in, an axial inner sideof the first partitionis formed as an inclined surface inclined relative to the axial direction, and an axial inner sideof the second partitionis formed as an inclined surface inclined relative to the axial direction and matching with the axial inner side. By arranging the abutting surfaces in the form of inclined surfaces, it can further facilitate the first sub-partand the second sub-partto hold each other and prevent them from being dislocated and deformed along the circumferential direction. In addition, it should be understood that even if such inclined surfaces are provided, they will not affect the formation of the recesses and the pins.

This non-planar axial sides design may also be used in combination with the embodiments of the present disclosure described above.

In addition, the present disclosure also provides some other improvements and deformations of the cage, and these improvements and deformations may also be used in combination with the above-mentioned embodiments.

According to one aspect of the present disclosure, an axial width ratio of the first partitionof the first sub-partto the second partitionof the second sub-partis 1:2 to 2:1.

According to this design, for example, when the axial width of the first partitionand the second partitionis 1:1, the first sub-partand the second sub-partcan be completely the same, which is beneficial to reducing the cost for processing and manufacturing, and the assembling process is simple. However, due to this structure, the maximum circumferential diameter of the ball is located at the interfacing seam of the axial inner sides between the first sub-part and the second sub-part, which sometimes causes the balls to be dislocated (this dislocation often occurs in steel cages of the prior art that need riveting). When the axial width ratio of the first partitionand the second partitionis 1:2 or 2:1, the pocket of one of the sub-partsorwill be relatively larger, so that the portion of the ball with the largest circumferential diameter can be enclosed by one sub-part, which prevents the ball from being dislocated.

According to another aspect of the present disclosure, the axial outer side of the first sub-partmay include a groove and/or the axial outer side of the second sub-partmay include a groove. Such grooves form material removal portions, which can further reduce the total weight of the cage.

Although the cage according to the present disclosure is described above by taking a deep groove ball bearing as an example, it should be understood that the concept of the present disclosure can also be applied to cages for other type rolling elements.